The invention relates to a process for the preparation of bone cement and to an apparatus for carrying out this process.
Bone cement serves to fix prostheses in the bones of human and animal bodies. A good and permanent bonding of the bone cement to a prosthesis and to the bone requires that the bone cement is satisfactorily prepared before introduction into the cavity of the bone concerned, which is to receive the prosthesis. This means, in particular, that the state of polymerization of the bone cement at the beginning of the introduction of the bone cement into the bone cavity is such that the processing of the bone cement which now takes place leads to the best possible, permanent anchoring of the prosthesis in the bone-cavity. The processing time, i.e., the time at the surgeon's disposal for carrying out all the required work to anchor the prosthesis in the correct position in the bone cavity, from the beginning of introduction of the bone cement into the bone cavity until the hardening phase of the bone cement begins and no longer permits any change in the position of the prosthesis, is to be fully sufficient.
Bone cement is in general produced by mixing of liquid methyl methacrylate monomer and pulverulent polymethyl methacrylate, possibly with the addition of hardeners and accelerators. However, bone cement can also be produced form any other suitable components.